The cost of a pen is three times the cost of a pencil. the cost of 4 pencils and 3 pens is $9.75. what is the cost of a pencil? the cost of a pen is three times the cost of a pencil. the cost of 4 pencils and 3 pens is $9.75. what is the cost of a pencil?

Which statements are true? check all that apply. the line x = 0 is perpendicular to the line y = –3. all lines that are parallel to the y-axis are vertical lines. all lines that are perpendicular to the x-axis have a slope of 0. the equation of the line parallel to the x-axis that passes through the point (2, –6) is x = 2. the equation of the line perpendicular to the y-axis that passes through the point (–5, 1) is y = 1.